MESOSCALE DISCUSSION 1803
   NWS STORM PREDICTION CENTER NORMAN OK
   0131 PM CDT SUN AUG 19 2007
   
   AREAS AFFECTED...EASTERN ID/WESTERN WY AND SOUTHWEST/CENTRAL MT
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 191831Z - 192030Z
   
   THREAT FOR STRONG WIND GUSTS AND POTENTIALLY SEVERE HAIL IS EXPECTED
   TO STEADILY INCREASE BY MID AFTERNOON ACROSS FAR EASTERN
   ID/SOUTHWEST MT INTO WESTERN WY/CENTRAL MT. WILL CLOSELY MONITOR FOR
   THE POSSIBILITY OF A SEVERE THUNDERSTORM WATCH...WHICH COULD BE
   NEEDED BY AROUND 20Z.
   
   LATEST SURFACE ANALYSIS FEATURES SYNOPTIC COLD FRONT TRANSITIONING
   EASTWARD ACROSS FAR WESTERN MT/CENTRAL ID AT MIDDAY...WITH AMPLE
   DOWNSTREAM PRESSURE FALLS ACROSS THE ID/MT/WY BORDER REGION. IN THE
   AMBIENT WARM SECTOR AHEAD OF THE COLD FRONT...A RELATIVELY MOIST
   AIRMASS REMAINS IN PLACE...WITH AMPLE INSOLATION/HEATING ALREADY
   LEADING TO A DEEPENING CUMULUS FIELD OVER THE HIGHER TERRAIN OF
   EASTERN ID/WESTERN WY/SOUTHWEST MT. GIVEN THE RELATIVELY POTENT
   NATURE OF THE UPSTREAM SHORTWAVE TROUGH CROSSING ORE INTO ID AND THE
   ASSOCIATED COLD FRONT...THE DEGREE OF LARGE SCALE LINEAR FORCING
   WOULD SUGGEST THAT THUNDERSTORMS SHOULD CONSIDERABLY INCREASE
   THROUGH MID AFTERNOON ACROSS FAR EASTERN ID/SOUTHWEST MT...AND
   EVENTUALLY INTO WESTERN WY AND PORTIONS OF CENTRAL MT. AS SAMPLED
   VIA AVAILABLE WSR-88D VWP DATA FROM POCATELLO/BOISE
   ID...INCREASINGLY STRONG WIND FIELDS THROUGH THE LOW TO MID
   TROPOSPHERE WILL FAVOR ORGANIZED STORMS LATER THIS
   AFTERNOON...INCLUDING THE DISTINCT POSSIBILITY FOR SOME SUPERCELLS.
   ALONG WITH STRONG WIND GUSTS AND THE POSSIBILITY OF SOME SMALL
   BOWING SEGMENTS...POTENTIAL FOR UPDRAFT ROTATION VIA DEEP LAYER
   SHEAR OF 40+ KT WILL BE CONDUCIVE FOR SEVERE HAIL.
   
   ..GUYER.. 08/19/2007
   
   
   ATTN...WFO...BYZ...GGW...RIW...TFX...SLC...PIH...
   
   46961094 47340873 45810814 44110858 41320968 42091180
   44431230